Independent wheel suspension for motor vehicles



' April 16, 1940.

v. VALLETTA I 2,197,163

INDEPENDENT WHEEL SUSPENSION FOR MOTOR VEHICLES Filed July 7, 1938 Patented Apr. 16, 1940 v 2,197,163 INDEPENDENT WHEEL SUSPENSION FOR MOTOR VEHICLES Vittorio Valletta, Turin, Italy, assignor to Flat Societa Anonima, Turin, Italy Application July 7, 1938, Serial No. 217,987- In Italy October 22, 1937 I 1 Claim. (c1. 26720) When, with independent wheel suspnsions for motor vehicles of the known type in which the wheel is connected to the vehicle frame by means of a pair of links, it is desired to dispense with complicated, expensive and clumsy transmission devices, the spring is generally arranged between the lower, longer link and an arm or bracket secured to the frame. In such an arrangement the spring deformations are smaller 10 than the extent of oscillation of the wheel, i. e. the degree. of resiliency of the suspension is limited and the arrangement of a hydraulic shock absorber within the spring coil acts as a disturber, because the spring axis is rocked at ll each oscillation and, on account of the reduced deformation of the spring, the liquid volume displaced cannot be considerable unless the diameter and, consequently, the size and weight/ of the spring are exaggerated. I

In coiled spring. suspensions of the so-called candlestick type, in which the wheel is connected to the frame by means of a sleeve movable on' a fixed vertical spindle, around which the spring is coiled, the above mentioned drawbacks are avoided. The spring deformation is equal to thelextent of oscillation of the wheel and the shock absorber may be located within the vertical spindle. However,,movement of the sleeve on the spindle is accompanied by considerable friction, the spindle is subjected to heavy stresses when sharp and sudden shocks occur, and the construction of the spindle and sleeve fin'finwh more expensive than that of a pair of s.'- The present invention provides a motor vehicle suspension of the type embodying a pair -of links and a coiled spring, characterized in that the spring is compressed between an arm or bracket attached to, the wheel and an arm a or bracket attached to the vehicle frame. with this arrangement, the spring deformation is practically equalto the extent of oscillation of the wheel and the spring is always substantially vertical as in a candlestick" suspension, so that the advantages of the candlestick" suspension are thus combined with those of the link quadrilateral type while the drawbacks ofboth types are eliminated. A hydraulic piston shock absorber is arranged within the spring coil.

By way of example a constructional embodiment of the invention is shOWD on the accompanying drawing. 1

Figs. 1 and '2 represent this embodiment dia-' grammatically in its two end positions.

Fig. 3 is a sectional view, on a larger scale, of

the suspension in an intermediate position'and as applied to a steering road wheel.

A link quadrilateral is formed by the arm I, which is a part of the axle 8 fixed on the vehicle frame, by the wheel support 2 opposite the arm I, and by upper and lower links 3 and 4 articulated at a, b, c, d, to the arm I and support 2, respectively. The upper link 3 is shorter than the lower one, as is usual in order to prevent or limit lateral dragging of the wheel on the ground during oscillations. The arm I and wheel support 2 have fixed thereto brackets 5, 6, respectively, the bracket 5 overlying, the bracket 6, and

,a coiled spring I is compressed between the two brackets.

With this arrangement, the spring deformations are practically equal to the oscillations of the wheel. The spring axis, as will be evident by comparing Figs. 1 and 2, deviates only slightly from the vertical in passing from the position of go minimum to that of maximum compression, so that a hydraulic telescopic or piston shock absorber may be located easily and satisfactorily within the spring.

According to Fig. 3, the wheel support 2 is '35 provided withan arm 9 which carries the king pin for a steering wheel. The lower link 4 carries a pad l3 of rubber or the like serving as a damper in the two end positions taken by the suspension as it is acted upon either by the bracket 6 (Fig. 1) or the arm I and bracket I (Fig. 2).

A hydraulic telescopic or piston shock absorber is mounted within the .coiled spring 1; its lower element I4 is articulated by means of a head In and ring ll of rubber to the bracket 6 and its upper element I2 is articulated to the bracket 5 by means of lateral pivots l5 disposed normally with respect to the shock absorber axis. The points of articulationof the shock absorber are situated very near the end coils of the spring, so that the axes of the spring and shock absorber substantially coincide at any degree of compression of the spring.

The unit is of light and compact construction, 4.5 so that an axle 8 may be fully equipped with the suspension for the two wheels and then easily and rapidly assembled to the vehicle frame by fitting Jthe connecting bolts through suitable holes provided in the-axle 8 and frame memm bers.

What I claim is:

Independent "wheel suspension *for motor" vehicles, comprising a paixucf links articulated to the vehicle frame, a wheel support member ar-; y

ticulated to the ends of said links and connecting them together, a. bracket on the wheel support, a bracket fixed to the vehicle frame, and a, resilient pad arranged on the lower link to act as .a damper against the bracket on the wheel support when the suspension reaches its maxi- VITTORIO VALLE'I'I'A. I 

